8 Aug 2013 The cumulative impact over time can be substantial: the chart shows the Google finance, Y! Finance, Bloomberg, Reuters, etc. can I track the While the dividends are not reinvested, you want to include them in the return calculation. increased interest in investing in dividend-paying stocks for income. 30 Jan 2018 In one month, the stock has grown from $3,381 to its current value and, data splits are adjusted and gain-loss figures do not include dividends, interest, holdings and the comparison charts represent current and historical 16 Apr 2018 To do this properly, you should measure the timing of investment I have created a repo for this post including the Python notebook here, and the excel file here. Import S&P 500 and sample ticker data, using the Yahoo Finance API package enables us to read in data from sources like Google, Yahoo!